1. Field of the Invention
The present invention relates to a device for cleaning ink-transfer cylinders within a rotary printing press.
2. Description of the Prior Art
From German application P 42 16 636, to which U.S. Pat. No. 6,006,666 corresponds, a device is already known for the repeated reactive erasing of the ink-bearing layer, i.e. of the organic substance parts, from the surface of an image-bearing printing form on a cylinder. This ink-bearing layer is produced, for instance, by a thermographic, ink-jet, or electrostatic process. For reuse, the material forming the printing locations must be removed or erased so that the surface of the printing form can again bear an image.
The erasing device taught by this reference has at least one nozzle, but preferably several nozzles arranged alongside of each other which can be connected together by a commercial high-pressure cleaning system. The erasing device is arranged in the printing press along the entire printing form width and over a region of the surface of the printing form. Since the printing form is passed rotating below the erasing device, the entire surface of the printing form can be erased. The nozzles of the erasing device are provided with a covering which is open towards the printing form and serves as protection of the environment. The covering defines a working space and is connected to a pump for removing both the water introduced into the working space and the coating which has been removed.
EP 0 368 177 B1, to which U.S. Pat. No. 5,154,121 corresponds, discloses a gravure cylinder in which a solid substance which can be liquefied by the action of energy is introduced into each cell of a raw form in an amount inversely proportional to the amount of ink to be transferred. After a printing has been effected, in order to reestablish the gravure printing form for a further design after the remaining ink has been washed off, an erasing device is applied, which liquefies the filling material in the cells by means of a source of heat and removes it by means of a wiping and/or blowing or sucking device.